Prof. W. King 0^1 Spirifer cuspidatus. 7 



impressions as they appear when magnified twenty diameters ; 

 and fig. 5 shows ^\q perforations similarly enlarged, precisely 

 in the order, and at the distance from one another, to make 

 the impressions answer to the centres of the perforations. 



It is also of some importance that the appearances which I 

 took for perforations are stated in my paper to occur " here 

 and there ' in " patches " — a statement completely corrohorated 

 by Dr. Carpenter himself, and singularly agreeing with his 

 remark, applicable to all the perforated specimens he has exa- 

 mined, that the perforations have a "patchy distribution." 



No. 2. — This specimen has been kindly lent to me by Mr. 

 Morton, F.G.S. &c., of Liverpool. Its locality is not known : 

 possibly it is from the west of Ireland. 



Four sections, all showing perforations, most of them agree- 

 ing with those of No. 1, except that they are in general larger, 

 which appears to have been caused by metamorphism. In one 

 section they are quite distinct, but in the others they are more 

 or less obscure. The perforations in the best section have a 

 dark granular infilling; and generally they have an indefinite 

 outline ; the darkest are the best defined. In two of the sec- 

 tions the contents of the perforations are for the most part pale 

 and subtranslucent ; and the perforations themselves are each 

 smTounded by a broadish encircling zone of what appear to be 

 granules or cellules, though the appearance seems to be due to 

 the ends of the fibres rising up around the perforations. In 

 one section the perforations have lost all characters as such, 

 each being unusually large (larger than those above referred 

 to), and appearing as if it were a mere aggregation of trans- 

 parent cellules or granules (fig. 6). In most of the sections 

 the fibres are subtranslucent and well displayed : they run 

 straight on or wind about, but sweep past the perforations 

 with scarcely any deviation. The sections were easily rubbed 

 down. 



No. 3. — Specimen presented by Dr. M'Coy. It is the one 

 represented under fig. 1. 



Of six sections, one shows no distinct perforations ; perhaps 

 one or two slightly opaque spots might be taken for them : 

 two others show something of the kind somewhat more ob- 

 scurely, but more numerously : in the fourth they are some- 

 what less obscure, and, besides varying much in size, they are 

 " scattering." The other sections are even less satisfactory. 

 The fibres are quite distinct. 



'' No. 4. — I succeeded in getting no more than three sections 

 from this specimen : only one of them shows what may be 

 perforations, of a light-brown colour, but no better than the 

 less '' obscure ones "in a section belonging to the last speci- 



